Dominant And Resesive Genes Flashcards
How is DNA structured?
Double stranded and double helix
Describe chromosomes in the nucleus
- A chromosome is a length of DNA
- chromosomes are arranged into pairs in the nucleus
- along the length of each chromosomes are coding regions called genes
What are genes
Genes are codes for a specific protein which gives us our unique characteristics.
What is genome
The genome of an organism is its entire genetic material of that organism
What is an allele
An allele is a different form of a gene
What is a dominant Allele
Dominant alleles are always expressed when they are present.
What are recessive alleles?
A recessive allele is only expressed when there are 2 of them and are represented with a lower case letter.
What is it when something is homozygous?
When an individual has 2 alleles of the same (e.g. BB, tt etc) this is called homozygous when they are the SAME!!!
What does it mean when something is heterozygous?
This is when a individual has 2 different alleles (e.g Bb, Tt etc) this is calles heterozygous DIFFERENT!!!
What is meant by phenotype?
This is used to describe the characteristics of what a baby or parents would have and describes the what aspects they have for example they could have a DISEASE X NORMAL.
What is it meant by Genotype?
This is the same as a phenotype but written differently for example HH X hh
What is genetic screening
the study of a person’s DNA in order to identify genetic differences or susceptibility to particular diseases or abnormalities.
